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Carlyle, IL, United States

Puls C.L.,Urbana University | Rojo A.,Urbana University | Ellis M.,Urbana University | Boler D.D.,Urbana University | And 6 more authors.
Journal of Animal Science | Year: 2014

The study used a randomized complete block design (blocking factor was date of start on test) with 5 treatments: 1) physically castrated barrows (PC), 2) intact males (IM), 3) gilts (G), 4) immunologically castrated barrows (IC), and 5) immunologically castrated barrows fed ractopamine at 5 mg/kg (IC+RAC). The study used 192 pigs and was performed from the 16 wk of age (67.2 ± 2.52 kg BW) to a pen mean BW of 132.5 ± 3.60 kg. For IC+RAC, ractopamine was fed for the final 23 d of the study. Pigs were housed in groups of 4 (10 groups for PC, IM, G, and IC and 8 groups for IC+RAC) in a finishing building at a floor space of 1.18 m2/pig. Diets were formulated to meet requirements of IM except that the diet for the IC+RAC fed during the ractopamine feeding period was formulated to meet requirements of pigs on that treatment. Pigs had ad libitum access to feed and water throughout the study period and were individually weighed at the start, wk 2 and 4, and subsequently every week until the end of study. For the overall study period, IC had greater (P ≤ 0.05) ADG than the other genders (1,150, 1,024, 1,064, and 954 g/d for IC, PC, IM, and G, respectively; SEM = 25.8) and required fewer days to reach slaughter weight than the other genders (58.1, 61.6, 61.6, and 66.5 d for IC, PC, IM, and G, respectively; SEM = 1.26). Overall ADFIwas less (P ≤ 0.05) for IM and G than IC and PC, which were similar (P > 0.05) in this respect (3.11, 3.06, 2.68, and 2.75 kg/d for IC, PC, IM, and G, respectively; SEM = 0.061). Overall G:F was greater (P ≤ 0.05) for IM than the other genders; IC had greater overall G:F than PC and G, which were similar in this respect (0.371, 0.335, 0.397, and 0.347 kg/kg for IC, PC, IM, and G, respectively; SEM = 0.0068). Immunologically castrated barrows had greater (P ≤ 0.05) ADG (30.7%) and ADFI(22.5%) than PC from the second week following the second Improvest dose to the end of the study. During the ractopamine feeding period, IC+RAC had greater (P ≤ 0.05) ADG (11.6%) and G:F (17.3%) than IC. The results of this study confirmed previously observed gender differences and effects of ractopamine on growth performance and that IC grew faster and had greater feed efficiency than PC during the study period. © 2014 American Society of Animal Science. All rights reserved. Source

Bohl Bormann N.L.,The Maschhoffs | Baxter C.A.,University of Wisconsin - Platteville | Andraski T.W.,University of Wisconsin - Madison | Good L.W.,University of Wisconsin - Madison | Bundy L.G.,University of Wisconsin - Madison
Soil Science Society of America Journal | Year: 2010

Frequently, well water is used instead of rainwater to perform rainfall simulations to study P and soil loss in cropping systems. This study was conducted to determine whether the source water used in simulated rainfall studies affects runoff amount and P and sediment concentrations. Rainfall simulation and natural runoff studies were conducted in a corn (Zea mays L.) and alfalfa (Medicago sativa L.) field on a Tama silt loam (fine-silty, mixed, superactive, mesic Typic Argiudoll) in spring and fall 2004. No significant differences in runoff composition were found between the well and deionized (DI) source waters in the spring rainfall simulation study in corn. The fall rain simulation in alfalfa showed significantly higher runoff volumes and dissolved reactive P (DRP) concentrations with DI water than with well water. Soil water-extractable P (WEP) measurements showed that rain and DI water extracted similar amounts of P, while well water extracted less P. Using the same source waters in WEP procedures and in rainfall simulations yielded good relationships (r2 = 0.73) between simulated rain runoff DRP and soil WEP concentrations. Natural runoff DRP concentrations measured in the same field treatments as those used in the simulated rainfall studies were much greater than those found in simulated rainfall runoff, but the relative field treatment effects on runoff P concentrations were the same. These results emphasize that simulated rainfall data can provide a relative comparison of treatment effects on runoff composition, but results from simulated rainfall experiments are not likely to duplicate natural runoff composition, regardless of the source water used. © Soil Science Society of America, All rights reserved. Source

Yoder C.L.,Iowa State University | Schwab C.R.,The Maschhoffs | Fix J.S.,National Swine Registry | Duttlinger V.M.,Tempel Genetics | Baas T.J.,Iowa State University
Livestock Science | Year: 2012

Daily feed intake during lactation was recorded on purebred Yorkshire (n=1587), Landrace (n=2197), and F1 Yorkshire x Landrace (n=6932) litters from day 1 to 22 of lactation. Lactation feed intake (LFI) curves were predicted using a mixed model which included fixed effects of breed, season, parity group (PG), day of lactation, interactions of day with breed and PG, and a covariate for litter size after cross-fostering. Random effects included litter, contemporary group (herd-year-month), dam, and sire nested within breed. Least squares means for each day were used to express LFI curves by breed through day 22 of lactation. Yorkshire and Landrace LFI curves were not different (P=0.09), though both differed from the LFI curve (P<0.05) of F1 sows. Due to a limited number of observations in late lactation, LFI data from days 19 to 22 were not included. Evaluation of the difference in feed intake between 2 consecutive days (DC) of lactation resulted in the following classifications: 3 periods for purebreds, day 1 to 6 (PB1), day 7 to 10 (PB2), and day 11 to 18 (PB3); 2 periods for F1 sows, day 1-5 (C1) and day 6-18 (C2). Average rate of change in intake (ARC), average daily intake (ADI), and variation from predicted LFI values (VAR) metrics were estimated for each period in purebred and F1 sows. Parity group 1 in both purebred and F1 sows had the lowest ARC and ADI metrics, but highest VAR (P<0.05) in each period of lactation. Similar differences were observed for seasonal effects (P<0.05) as LFI curves during summer months represented lower ARC and ADI and higher VAR values compared to all other seasons. For all breeds, increased ARC and ADI metrics resulted in higher 21-day litter weaning weights (P<0.05), while decreasing VAR metrics late in lactation (PB3 and C2) resulted in higher 21-day litter weaning weights and shorter wean-to-first service intervals (P<0.05). Average rate of change increased more quickly in early periods (PB1, PB2, C1) and was lower in late lactation (PB3, C2). An increase in average rate of change in intake, average daily intake, and decreased variation from predicted LFI values during a period of lactation resulted in improved measures of maternal performance. © 2012 Elsevier B.V. Source

Yoder C.L.,Iowa State University | Schwab C.R.,The Maschhoffs | Fix J.S.,National Swine Registry | Stalder K.J.,Iowa State University | And 3 more authors.
Livestock Science | Year: 2013

The objectives of this study were to quantify significant negative deviations (DEV) from predicted daily lactation feed intake values and to estimate their effect on reproductive performance and subsequent intake in purebred and F1 sows. Daily lactation feed intake (LFI) records from day 1 to 22 of lactation from purebred Yorkshire (n=1587 parity records), purebred Landrace (n=2197 parity records), and reciprocal cross F1 (n=6932 parity records) females were used to predict daily LFI values. The mixed model included fixed effects of breed, season, parity group (1, 2, 3 and ≥4), day of lactation, and interactions of day with breed and parity group, and a covariate of litter size after cross-fostering. Random effects included litter, contemporary group (herd-year-month), dam, and sire nested within breed. Deviations from predicted LFI values were quantified using an internally studentized residual (SR). A SR≤-1.71, equivalent to observed LFI at least 1.9. kg less than predicted, was considered a DEV. Zero DEV occurred in 60% of lactation records, while 18% of lactation records had 1 DEV, and 22% of lactation records had ≥2 DEV. Thirty-four percent of negative deviations occurred during the summer months (June, July, August) which was more frequent when compared to the spring (26%), fall (23%), and winter (17%) months. Adjusted 21-day litter weaning weight (LW21) decreased as the number of DEV increased within a single lactation period, and wean-to-first service interval (WTSI) increased when at least 3 DEV occurred within a single lactation. An increase in DEV during early lactation did not affect LW21 or WTSI (P>0.05), though an increase in number of DEV after day 5 of lactation was associated with lower LW21 and longer WTSI. Odds of a negative deviation from predicted LFI occurring on any given day of lactation were estimated as odds ratios. If a DEV occurred the prior day, a DEV was 8.7 and 39.5 times more likely to occur than if a DEV had not occurred for purebred and F1 sows, respectively. In F1 sows, a DEV was 3.1 (P<0.01) times more likely to occur after day 5 of lactation when a DEV occurred on day 1 to 5 of lactation. Negative deviations from predicted LFI values decreased reproductive performance and had a larger effect on performance when they occurred during late lactation. © 2013 Elsevier B.V. Source

Badke Y.M.,Michigan State University | Bates R.O.,Michigan State University | Ernst C.W.,Michigan State University | Schwab C.,The Maschhoffs | And 3 more authors.
BMC Genetics | Year: 2013

Background: Genotype imputation is a cost efficient alternative to use of high density genotypes for implementing genomic selection. The objective of this study was to investigate variables affecting imputation accuracy from low density tagSNP (average distance between tagSNP from 100kb to 1Mb) sets in swine, selected using LD information, physical location, or accuracy for genotype imputation. We compared results of imputation accuracy based on several sets of low density tagSNP of varying densities and selected using three different methods. In addition, we assessed the effect of varying size and composition of the reference panel of haplotypes used for imputation.Results: TagSNP density of at least 1 tagSNP per 340kb (~7000 tagSNP) selected using pairwise LD information was necessary to achieve average imputation accuracy higher than 0.95. A commercial low density (9K) tagSNP set for swine was developed concurrent to this study and an average accuracy of imputation of 0.951 based on these tagSNP was estimated. Construction of a haplotype reference panel was most efficient when these haplotypes were obtained from randomly sampled individuals. Increasing the size of the original reference haplotype panel (128 haplotypes sampled from 32 sire/dam/offspring trios phased in a previous study) led to an overall increase in imputation accuracy (IA = 0.97 with 512 haplotypes), but was especially useful in increasing imputation accuracy of SNP with MAF below 0.1 and for SNP located in the chromosomal extremes (within 5% of chromosome end).Conclusion: The new commercially available 9K tagSNP set can be used to obtain imputed genotypes with high accuracy, even when imputation is based on a comparably small panel of reference haplotypes (128 haplotypes). Average imputation accuracy can be further increased by adding haplotypes to the reference panel. In addition, our results show that randomly sampling individuals to genotype for the construction of a reference haplotype panel is more cost efficient than specifically sampling older animals or trios with no observed loss in imputation accuracy. We expect that the use of imputed genotypes in swine breeding will yield highly accurate predictions of GEBV, based on the observed accuracy and reported results in dairy cattle, where genomic evaluation of some individuals is based on genotypes imputed with the same accuracy as our Yorkshire population. © 2013 Steibel et al.; licensee BioMed Central Ltd. Source

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